Originally Posted by Dirty_Idea

I find the cryptic answer to the question of miles cost to be really odd. OP asked how much it cost. If the employee had given him a straight answer there wouldn't have been an issue here. OP isn't obliged to know how many miles it costs by checking up front and his failure to do so is pretty much irrelevant. The employee should have answered with "yes, an upgrade is possible and will cost X miles, would you like me to proceed?" At the very least they should have answered the "what did this cost?" with a simple "x miles". The answer given makes it sound like OP has been given some sort of deal, or that the employee is being playful in providing some sort of extra.

If I went into a store and, having just handed over my card to pay for my TV, I enquired if they had a service package, I'd be pretty narked if they replied with "done!!!" and when I asked what they'd charged my card they told me "I can't tell you, ho ho ho". I mean really. These miles cost a packet to buy, what kind of answer is "I can't tell you"? Imagine if you'd asked if you asked if they had cash upgrades and they replied with "done" and "I can't tell you".

I tend to agree with OPs read of the situation. My assumption would be that I had a free upgrade, not that for reasons unknown the staff member was refusing to tell me how much I'd been charged for a product I hadn't agreed to buy. So I'd probably also take my seat thinking "Bonus, an op-up".

OP, I'd go ask them to restore the miles. You already have "no" so what do you have to lose?